Pottery Kiln

[JoeStillman]

Wattage will be proportional to the square of the voltage. A resistive heater kiln rated for 240V will draw 208²/240² or 75% of the rated power. It will be able to get to the same temperature, just 33% slower.

 

[drcampbell]

... It will be able to get to the same temperature, just 33% slower.

Or it might never achieve the desired temperature, if the heat loss at the desired temperature is more than the heating elements' output at the lower voltage.

 

[winnie]

If the ramp up time is outside of spec the computer detects that something is wrong, throws an error message, and stops the program. The customer looks in the manual and is told they need to have someone replace the elements and/or the relays. So in general, 240V elements won't work on 208V.

Annoying, given that the software could easily have a mode that checks for expected heating rates when operated on 208V.

-Jon

 

[drcampbell]

Annoying, given that the software could easily have a mode that checks for expected heating rates when operated on 208V.

-Jon

Poorly-designed software? Unprecedented!

 

[JoeStillman]

You would only need a 3 kVA 120x240 : 12x24 autotransformer to step it up from 208V to 240V. Check out https://solahevidutysales.com/buck_boost_transformers.htm

 

[Jraef]

Or it might never achieve the desired temperature, if the heat loss at the desired temperature is more than the heating elements' output at the lower voltage.

Unlikely in a kiln though.

Kilns are DESIGNED to retain heat. I’ve done SCR controllers for kilns whether people wanted to lower the final temperature without the constant on-off cycling. They were shocked to discover that they had to be down around 30% of rated watts before it made a significant difference (other that the time it took to get to temp).